972 research outputs found
For operation of the Computer Software Management and Information Center (COSMIC)
During the month of June, the Survey Research Center (SRC) at the University of Georgia designed new benefits questionnaires for computer software management and information center (COSMIC). As a test of their utility, these questionnaires are now used in the benefits identification process
Four Decades of Computing in Subnuclear Physics - from Bubble Chamber to LHC
This manuscript addresses selected aspects of computing for the
reconstruction and simulation of particle interactions in subnuclear physics.
Based on personal experience with experiments at DESY and at CERN, I cover the
evolution of computing hardware and software from the era of track chambers
where interactions were recorded on photographic film up to the LHC experiments
with their multi-million electronic channels
The ESPRI project: astrometric exoplanet search with PRIMA I. Instrument description and performance of first light observations
The ESPRI project relies on the astrometric capabilities offered by the PRIMA
facility of the Very Large Telescope Interferometer for the discovery and study
of planetary systems. Our survey consists of obtaining high-precision
astrometry for a large sample of stars over several years and to detect their
barycentric motions due to orbiting planets. We present the operation
principle, the instrument's implementation, and the results of a first series
of test observations. A comprehensive overview of the instrument infrastructure
is given and the observation strategy for dual-field relative astrometry is
presented. The differential delay lines, a key component of the PRIMA facility
which was delivered by the ESPRI consortium, are described and their
performance within the facility is discussed. Observations of bright visual
binaries are used to test the observation procedures and to establish the
instrument's astrometric precision and accuracy. The data reduction strategy
for astrometry and the necessary corrections to the raw data are presented.
Adaptive optics observations with NACO are used as an independent verification
of PRIMA astrometric observations. The PRIMA facility was used to carry out
tests of astrometric observations. The astrometric performance in terms of
precision is limited by the atmospheric turbulence at a level close to the
theoretical expectations and a precision of 30 micro-arcseconds was achieved.
In contrast, the astrometric accuracy is insufficient for the goals of the
ESPRI project and is currently limited by systematic errors that originate in
the part of the interferometer beamtrain which is not monitored by the internal
metrology system. Our observations led to the definition of corrective actions
required to make the facility ready for carrying out the ESPRI search for
extrasolar planets.Comment: 32 pages, 39 figures, Accepted for publication in Astronomy and
Astrophysic
Translating expert system rules into Ada code with validation and verification
The purpose of this ongoing research and development program is to develop software tools which enable the rapid development, upgrading, and maintenance of embedded real-time artificial intelligence systems. The goals of this phase of the research were to investigate the feasibility of developing software tools which automatically translate expert system rules into Ada code and develop methods for performing validation and verification testing of the resultant expert system. A prototype system was demonstrated which automatically translated rules from an Air Force expert system was demonstrated which detected errors in the execution of the resultant system. The method and prototype tools for converting AI representations into Ada code by converting the rules into Ada code modules and then linking them with an Activation Framework based run-time environment to form an executable load module are discussed. This method is based upon the use of Evidence Flow Graphs which are a data flow representation for intelligent systems. The development of prototype test generation and evaluation software which was used to test the resultant code is discussed. This testing was performed automatically using Monte-Carlo techniques based upon a constraint based description of the required performance for the system
Monitoring Time Intervals
Run-time checking of timed properties requires to monitor events occurring within a specified time interval. In a distributed setting, working with intervals is complicated due to uncertainties about network delays and clock synchronization. Determining that an interval can be closed - i.e., that all events occurring within the interval have been observed - cannot be done without a delay. In this paper, we consider how an appropriate delay can be determined based on parameters of a monitoring setup, such as network delay, clock skew and clock rate. We then propose a generic scheme for monitoring time intervals, parameterized by the detection delay, and discuss the use of this monitoring scheme to check different timed specifications, including real-time temporal logics and rate calculations
Flow Control Applications
Flow control has a long history with many successes across a plethora of applications. This report addresses the characteristics of the approaches that are actually used, why they are used, the many approaches that are not used, and why. Analysis indicates ways forward to increase applicability/usefulness, and efficiency of flow control research. Overall, greater and more effective progress in flow control requires utilization of far more detailed information early in the research process regarding application details and requirements
Pinvox Method to Enhance Self-Study in Blended Learning: Experiences at University of Bucharest
We report results on the first large-scale trial implementation of the new Pinvox algorithm carried out at the Department of Distance Learning (DL) of the University of Bucharest to encourage hundreds of Bachelor and Master DL students to perform their self-study. Pinvox is an open source tool that helps to ensure "on-line attendance" and to induce "student's attention��� through the identification of different, randomly selected, brief audio PINs embedded automatically in videos or audio files assigned to each student. We argue that checking how students watched a video lecture has many advantages in the formative assessment work
The STAR MAPS-based PiXeL detector
The PiXeL detector (PXL) for the Heavy Flavor Tracker (HFT) of the STAR
experiment at RHIC is the first application of the state-of-the-art thin
Monolithic Active Pixel Sensors (MAPS) technology in a collider environment.
Custom built pixel sensors, their readout electronics and the detector
mechanical structure are described in detail. Selected detector design aspects
and production steps are presented. The detector operations during the three
years of data taking (2014-2016) and the overall performance exceeding the
design specifications are discussed in the conclusive sections of this paper
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